Hello,
That's a messy situation, I need to clear up a few details to give you the right steps.
First, when you say you had to create a new account, how exactly did you do that if you couldn't log into the computer? Did you reinstall Windows, use Safe Mode, or do something else?
Second, regarding the BitLocker key, did you check the specific recovery key page at account.microsoft.com/devices/recoverykey using any email you might have used? (even school or work ones)
Lastly, does the original account on the login screen give you an option to sign in with a PIN or password instead of the face scan, or is that option missing entirely?